Hydrostatic loop

A hydrostatic loop, though not often used in plumbing practice, is an arrangement of pipes formed into a vertical loop to prevent backflow of water within the plumbing potable water system. Since a siphon has a maximum height that it can work (about 33 feet), a hydrostatic loop is built higher than 33 feet. There are several ways to prevent siphonage and an undesirable backflow of the water in a plumbing system. The design relies on gravity and atmospheric pressure rather than mechanical devices, making it a passive method of backflow prevention. However, due to its impractical height and space requirements, the hydrostatic loop is rarely used in modern installations, where mechanical backflow preventers or air gaps are preferred. Vented loops

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A hydrostatic loop, though not often used in plumbing practice, is an arrangement of pipes formed into a vertical loop to prevent backflow of water within the plumbing potable water system. Since a siphon has a maximum height that it can work (about 33 feet), a hydrostatic loop is built higher than 33 feet. There are several ways to prevent siphonage and an undesirable backflow of the water in a plumbing system. The design relies on gravity and atmospheric pressure rather than mechanical devices, making it a passive method of backflow prevention.^[1] However, due to its impractical height and space requirements, the hydrostatic loop is rarely used in modern installations, where mechanical backflow preventers or air gaps are preferred.

Vented loops ^[2]

References

[edit]

^ "Plumber System". Plumbing and Drains. Retrieved 2025-10-24.
^ "HVL and PVL Series Vented Loops" (PDF). .groco.net. Archived from the original (PDF) on 27 March 2014. Retrieved 26 March 2014.

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Hydrostatic loop

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